Chris Heger, Chief Innovation Officer, OAC Services
One of the definitions of Technology,“Is the application of scientific knowledge for practical purpose, especially in industry”. It is knowledge, its capture, storage, transfer and analysis that has been and will continue to transform our industry for the better. In my 32 years in the industry spanning from stadia wires on theodolites to digital twins and robotic layout, it has always been knowledge and its application that has been the foundation for every advancement in the industry. Today, we have exponentially more access to knowledge than anytime in our history, and our industry as a whole, needs to embrace technology as knowledge capture, storage, and transfer tool in order to satisfy the built environment needs of society.
The digital twins that are being generated today the provide the structure to capture, store and transfer that knowledge by storing the information in code rather than concrete. We need to move away from the concepts of projects and look at them as part of a (PIM) Portfolio Information Strategy. For the majority of us who are builders are projects are not unique, they are made up of interchangeable elements which translate to interchangeable partsand each part has information that can be attached to both the digital element and physical part.
The design and construction of the digital twin is what is the difference between building today and building in the past. “Build it in the model.” is the mantra for the modern builder because we are only assembling at the site, because the elements are being manufactured at factories located all over the world. The data is structured by coordinates that are used in the model, CNC machines,
Total stations, machine control heavy equipment and robotic layout units. The primary key of every element digital and physical is the Northing, Easting and Elevation unique to it.
In the built environment the digital twin is a graph database that can be used as the digital truth for the entire project through inception to the end of the useful life of the structure, but the knowledge stored in the twin can be used as a reference class and teaching tool until the knowledge is replaced by improved knowledge.
Much of the knowledge that is revolutionizing our industry today is based on knowledge that has been known for decades. (TSP) the traveling salesman problem that is used by robots performing layout on construction sites now in order to find the shortest distance to travel was first developed in the 1930’s, and this knowledge could be used for project planning of workers and equipment on all projects if the knowledge was more widely known and applied. Bayes theorem developed by Thomas Bayes in the 1700’s and widely used in other industries is being applied on some projects today in scheduling and risk, but should be commonly used across all projects small, large and Mega.But the most important key about these algorithms being used today is when they are utilized in code the knowledge can be more easily transmitted across space and time. This latest generation learns faster because of digitized knowledge resulting in greater improvements that are stored in the structure of the digital twins.
Digital twins are Graph Databases which store nodes and relationships instead of tables and documents, which I see greatly improving scheduling and planning in the design and construction industry. The model is the structure providing the location of the elements, but the schedule is the time, how, and who of performing work. When I started in this industry in 89 and started building schedules in the early 90’s those who were behind schedule and over budget were not employed very long. I had a great teacher and learned that all schedules are a mathematical algorithm with activities based on number of units multiplied times unit rate of install divided by installing systems.
The estimate would give one units and unit cost that was used to validate the schedule. Schedule logic was based on location proximity, knowledge and understanding of how elements are attached. Regression was used to calculate activity duration and measure unit cost.
Today, the projects are much more complex with mahogany finishes replace by IT and AV, and our industry needs to embrace more advanced scheduling techniques than a Gantt Chart that was developed in the early 1900’s for time and motion study. The digital twin will allow the modern builder to have in one database scope, schedule and cost in order to ensure no scope gaps, to avoid the planning fallacy (D. Kahneman, A. Tversky) and to store the knowledge of the execution for reuse.
Reuse is a word for MDO or gang panels on a project, but not often in terms of schedules. However, construction is manufacturing, and the industry needs to use scheduling from manufacturing such as Littles Law,Job Shop Scheduling, Theory of Constraints, and Six Sigma to improve the schedules and throughput of projects and portfolios. Interchangeable parts tied to interchangeable information that includes scheduling with regression to the mean unit rate of install data. Real time telemetry on the site, on the supply chain and at the factory to synchronize all the work around the world associated with the project. The repeatable parts create normalized schedule data that can be compared to other projects in the portfolio and analyzed with histograms and control chart to define standards and find opportunities.
At OAC we have been exploring the relationship of the model, schedule and estimate in AZURE SQL for several years looking for opportunities in preparation for use in digital twins. The results have been promising and we have developed forecasting graphs that have changed the course of projects for positive outcomes. However, design and construction is a complex system and only as good as its weakest link or node, and that is why the digital twin (graph database) provides a paradigm shift for the industry. The digital twin provides a structure for the whole system, in order to improve an area for the betterment of the whole and the storing and transmission of that knowledge for reuse.